OCEAN COiS[TOURS, S.W. PACIFIC. 437 



unconformity between Jurassic and Triassic rocks. The late Jurassic 

 was the critical period in New Zealand. Since that period New 

 Zealand has been essentially the same in outline and configuration, 

 though elevations and depressions have repeatedly changed its extent. 

 Though the main direction of the folds is as stated, Fraser has 

 I'ccently shown that in the Coromandel the strike is almost due N. 

 and S., while on the western side, at Kawhia, Hochstetter long ago 

 found a N.E. strike, and his observations have been confirmed by 

 McKay. 



Of earth movements later than this there have been many, and 

 in New Caledonia they have been important. The Cretaceous coal 

 deposits of that island are apparently not separated by any important 

 unconformity from the Triassic, and have been involved in the same 

 movements, a statement which points to rather later folding than in 

 New Zealand, though here, too, the folding was continued into the 

 Cretaceous. 



Plutootc Rocks. 



The presence of Plutonic rocks in any land surface must always 

 be evidence of great erosion. The fact that such rocks occur at or 

 above the sea level suggests that in many cases elevation has taken 

 place in such an area. Since the Plutonics have been covered by 

 other rocks their elevated position may be due to folding. It is 

 impoitant, therefore, to record the areas where Plutonic rocks are 

 found in the South-west Pacific. There are, of course, many outcrops 

 in Australia and New Zealand, and it is unnecessaiy to refer further 

 to these. 



Gabbro is found in Campbell Island. 



Gabbro and granite in the Auckland group. 



The Snares are fomied of granite. 



The Bounty Islands are composed of granite alone. 



On Tahiti nepheline syenite occurs. 



Granite has been recorded from Sunday Island in the Kermadecs 

 by Thomas. 



Anuralitised gabbro comes from Tonga. 



Woolnough has recorded much plutonic I'ock from Viti Levu, and 

 mentions that at Aneityum, Espiritu Santo, and Malicolo in the New 

 Hebrides plutonics or their derivatives occur. 



In New Caledonia there is a great mass of seiijentine almost 

 certainly derived from* ultra basic rocks of plutonic nature. 



Earth Movemekts Since the Cainozoic. 



In the Cainozoic era a large part of the S.W. Pacific must have 

 been at a far lower level than it is now. 



The three regions in particular in which we have evidence of »this 

 are Fiji, New Hebrides, and New Zealand. 



In Fiji, Woolnough describes marine soapstones as elevated at 

 the present time to a height of 4,000 ft. above sea level. The age is 

 not further stated than that they are certainly Tertiary. They cover 

 the old rocks so completely that it is only in deep valleys and other 

 places where erosion has been rapid that the plutonic rocks and slates 

 are to be seen. During the deposition of these rocks the old erosibn 



